Volcanic Activity in Mexico During the Holocene

Abstract

This chapter presents an overview of the volcanic eruptions that have occurred in Mexico during the Holocene. Although volcanic regions are distributed all over the country, Holocene eruptions are mainly concentrated in the southern half of the country and, in particular, in the Trans-Mexican Volcanic Belt. Here, we summarize the details of the eruptions from the stratovolcanoes and monogenetic volcanoes, which have been extensively documented in the volcanological literature, and their radiometric or historical dates. Out of the 153 Holocene eruptions described so far, ~63.4% have occurred at active stratovolcanoes and calderas, while the remaining ~36.6% have occurred from vents within monogenetic volcanic fields. Surprisingly, it seems that volcanism increased through time from Early (~17.7%), Middle (~26.8%) to Late Holocene (~55.5%). These figures may be biased because younger deposits are better preserved than older ones, and the latter usually are eroded through time especially around active stratovolcanoes. Around 24 eruptions (~15.6%) have taken place in pre-Hispanic and historical time out of which 11 occurred during the Little Ice Age. These eruptions have posed a serious threat to the surrounding regions and their populations. Some stratovolcanoes have collapsed at least once, covering and destroying previous deposits and making it difficult to reconstruct past eruption records. Large, Plinian to sub-Plinian eruptions at stratovolcanoes are well recorded in the stratigraphy, but the small eruptions that did not produce widespread deposits are difficult to define. Eruptions from monogenetic volcanic fields were fed from central vents and fissures and mostly dominated by Strombolian activity and lava flows. The Holocene-collected data suggests that an eruption has taken place every ~65 years in Mexican territory during the past 10 ka. Monogenetic volcanoes should not be underestimated because at least 56 volcanoes have been created in Mexico during the Holocene, yielding an average recurrence of ~176 years. This chapter stresses the need to improve our knowledge of Holocene volcanism (e.g. still limited studies in some volcanoes) aimed to define average recurrence intervals and provide the data for probabilistic studies and hazard assessment to reduce future volcanic hazards.